The present invention relates to a reservoir of gaseous fuel in liquid phase and more particularly to a removable reservoir or cartridge for an apparatus using the combustion of this gas.
Such a reservoir, which is generally of cylindrical shape, has a filling orifice at the centre of its bottom and, at its end opposite the bottom, a draw-off orifice equipped with a draw-off member such as a valve and with an pressure reducer/evaporator, such as a porous element of permeability suited to the desired flow rate.
The objective to be achieved is to store the greatest quantity of fuel in liquid phase in this reservoir, without it being-possible for the liquid phase to reach the pressure reducer, which would cause spluttering deleterious to correct functioning of the apparatus onto which this reservoir is fitted.
One solution consists in storing the liquefied fuel in an absorbant in which it is retained in the liquid state by capillary forces. The absorbant is characterized by its nature and its density; it may also be characterized, in use, by the capillary rise of the absorbed liquid when equilibrium is reached, that is to say when the gravitational forces are balanced by the capillary forces.
The document EP-A-0 202 172 relates to a reservoir for liquid gas, entirely filled with an absorbent material, inside which there is provided a perforated central duct in which a dip tube, intended for the outlet of the gas from the reservoir, is engaged with a clearance.
The document EP-A-0,447,330 relates to a reservoir of fuel stored in liquid phase, the fuel being trapped within a porous or fibrous substance filling the reservoir. This reservoir comprises a dip tube connecting the outlet orifice to the centre of the reservoir.
A certain number of absorbent media have been tested and the capillary rise measured is of the order of 100 mm. This height of capillary rise therefore determines, depending on the other dimensions, the maximum capacity of liquid absorbed.
If the greatest dimension of the reservoir is greater than this 100 mm value, it is not possible to fill the reservoir beyond this .maximum capacity without running the risk of having fuel in free-liquid phase which may reach the pressure reducer, especially if the reservoir is held with its draw-off orifice in the down position.